August kampf



Patented July 11, 189 3.

@N q R W h A Q Ah R Q N n A. KAMPP. HYDRAULIC PRESS, 8w.

UNITED STATES ATENT OFFICE.

AUGUST KAMPF, OF MAGDEBURG, GERMANY, ASSIGNOR TO THEGRUSON- WVERK, OFSAME PLACE.

HYDRAULIC PRESS, 800.

SPECIFICATION forming part of Letters Patent N 0. 501,426, dated July11, 1893.

Application filed October 5, 1892. Serial No. 44:7,877. (ITO model.)Patented in England January 6, 1891 No. 9,640; in Germany March 26, 1891No. 59,298, and in Italy June 30, 1891 LVIII, 406.

To all whom it may concern:

Be it known that 1, AUGUST KAMPF, a subject of the King of Prussia, anda resident of Magdeburg, in theKingdom of Prussia, Empire of Germany,have invented new and useful Improvements in and Relating to HydraulicPresses having Telescopic Pistons, (for which I have obtained LettersPatent in Germany, No. 59,298, dated March 26, 1891; in Great Britain,No. 9,640, dated January 6, 1891, and in Italy, Registro Attestate, Vol.LVIII, No. 406, dated June 30,1891,) of which the following is aspecification.

This invention relates to apparatus for effooting the return movement ofa telescopic piston in a hydraulic press, after the outward stroke hasbeen completed, by the fluid underpressure. In presses having a singleor simple piston, the return movement can be provided for, as is wellknown, by making the piston not in the form of a plunger, but as adouble-actin g piston, and conducting the fluid under pressure (afterthe completion of the outward stroke and after the opening of theexhaust valve of the cylinder) into the annular space in front of thesaid piston. The problem becomes more difficult if, by reason of localconditions, it is necessary to employ a telescopic piston. The presentinvention solves this problem by the construction of the several partsor sections of the telescopic piston as double-actin g pistons, and theprovision of suitable means whereby the annular spaces in front of theseveral sections may be connected by a common pipe with the force-pumps,the accumulator orthe pressure-main on the one hand, and with theexhaust reservoir or main on the otherhand.

In the drawings is representeda press having a telescopic piston formedof three parts or sections, and constructed according to this invention.

Figure l is a central longitudinal section of the said press and Fig. 2is a transverse section on the line or, m, Fig. 1.

To the press-cylinder A which is made in one piece with a second smalleror auxiliary cylinder B arranged parallel therewith, the fluid underpressure is conducted through a .device.

communicates, through a channel b at the front end of the'press-cylinderA with the auxiliary cylinder B. The annular space 0 in front of thesecond piston E also communicates with the cylinder B, through a channeld in the wall of the largest piston D at the front end of the same, andthrough a suitable pipe G., The pipe G extends into the auxiliarycylinder B, through a stuffing gland, and is firmly connected with thepiston D so that it must participate in the movement of the latter. Inlike manner, the annular space e in front of the smallest piston F is incommunication with the cylinder B through a channel f and through a pipeI-I,

which extends through a stuffing gland in the head g of the pipe G. Thepress cylinder A, moreover, communicates with one of the four ways ofthe cock 0 through a pipe 1'. The transverse section of the annularspace 0 is somewhat larger than the transverse section of the pipe G,and the transverse sect-ion of the space e is somewhat larger than thetransverse sectionof the pipe H. The. capacity of the fluid space in thecylinder B will be greatest and therefore in the annular spaces a c esmallest when the telescopic piston is completely extended, and smallestin the cylinder B and greatest in the spaces a c 6, when the saidtelescopic piston is completely pushed in or contracted. The differencebetween the greatest and smallest capacity is kept slight in order tosave as much water under pressure as practicable for effecting thereturn movement of the piston. The cylinder B communicates with the fourway cock 0 by a pipe h, and the press cylinder A communicates with thesaid cock by a pipe 1.

I, J, Fig. 2, are the supply and exhaust pipes respectively leading toand from the cock 0.

der B and pushes together or closes the telescopic piston andconsequently the pipes G and H. lVhen the plug of the cock is turned sothat the cylinder A again receives fluid under pressure, and thecylinder B is connected with the exhaust, the pistons D, E and F aremoved outward, the piston D carrying with it the pipe G and the piston Ecarrying with it the pipe H. The annular spaces a, c and e thus becomegradually contracted, and the liquid contained in them escapes throughthe channels into the increasing space in the cylinder B while only asmall portion of the same flows to the exhaust through the pipe h.

Having now particularly described my inveution, what I claim is 1. Ahydraulic press having a telescopic piston and an auxiliary cylinder,and telescopic pipes making communication between the annular spaces infront of the respective parts of the telescopic piston and the saidauxiliary cylinder, substantially as and for the purpose set forth.

2. The combination of a pressure cylinder and an auxiliary cylinder, adouble-acting telescoping piston working in said pressure cylinder,sliding pipes working in said auxiliary cylinder, and having permanentcom-- munication respectively with the spaces in front of the parts ofthe said telescoping piston, and means for supplying pressure to eithercylinder at will, as and for the purpose set forth.

3. The combination of a pressure cylinder, a telescoping piston workingin said pressure cylinder and consisting of the double-acting sections,an auxiliary cylinder, sliding pipes Working in said auxiliary cylinderand permanently attached to the respective sections of the telescopingpiston, and having communication with the spaces Within the same,substantially as and'for the purpose set forth.

4:. The combination with the pressure cylinder, and the concentrictelescoping piston sections each having a space in front of its rearend, and movable one within another; of the parallel auxiliary'cylinder,having communication with the space in front of the outer section of thetelescoping piston, concentric telescoping pipes working in theauxiliary cylinder and connected with the sections of the telescopingpiston and establish- .ing communication between the spaces in front ofthe sections and'the auxiliary cylinder; and the four-way-cock havingducts communicating with the pressure supply and exhaust, allsubstantially as and for the purpose set forth.

AUGUST KAMPF.

Witnesses:

HERMANN L UBOWSKI,

EMIL KALLNEOKER.

